Question

In the synthesis of ammonia by Haber's process, if $60$ moles of ammonia is obtained in one hour, then the rate of disappearance of nitrogen is:

• A. $\text{30 mol/min}$
• B. $\text{6 mol/min}$
• C. $\text{0} \text{.5 mol/min}$
• D. $\text{60 mol/min}$

Answer 1

Answer: (C)

In Haber's process, ammonia is synthesized as

$\text{N}_{2}+3\text{H}_{2}\frac{\text{F} \text{e} , \text{M} \text{o} , 300 \text{℃}}{\text{H} \text{i} \text{g} \text{h} \, \text{P} \text{r} \text{e} \text{s} \text{s} \text{u} \text{r} \text{e}} \rightarrow \, 2\text{N}\text{H}_{3}$

Rate of synthesis of ammonia = $\frac{60}{60}$

$=\text{1 mol/min}$

$\therefore $ Rate of disappearance of nitrogen, i.e.,

$\frac{- \text{d} \left[\right. \text{N}_{2} \left]\right.}{\text{d} \text{t}}=\frac{1}{2}\frac{\text{d} \left[\right. \text{N} \text{H}_{3} \left]\right.}{\text{d} \text{t}}$

$=\text{0}\text{.5 mol/min}$